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newt help
Hi,
I've finally started build of the 10" F4 truss OTA.
But I need some clarification with newt calculations to work out ota length.
Attached are values I've entered in newt.
What I don't understand is the "Focuser camera travel". from newt help "enter the amount of additional height for the focal plane above the focal plane used for eyepieces"
I've specified the focal point for eyepieces to 20mm from the tip of the focuser. I don't get why I need to add additional distance to a ccd plane.
I thought the CCD would need to be at the focal point.
other bit is illumination field.
with the specs provided, I get a 100% illuminated dia of 15mm.
the qhy8 sensor is 28.4mm diagonal.
should the 100% illuminated field be as close to the sensor diagonal as possible? what should I change to get this right?
Thanks
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